Carbonation tank



Dec. 7, w43.

-o.' c. SWAN GARBONATION TANK Filed may 1, 12342 2 Sheets-Sheet 1 OL M5@C.

rliiateuited E9 NEE STATES PATE-NT .@FF-

j 2,336,199 'cAanoNA'rroN TANK oliver o. swan, betterave, com.application Moy 1, 1942, serial No.' 41,387

l y 10 Claims. This invention relates to a carbonation tank for use insugar mills and has for its principal object the provision of a single,unitary tank'with which both the liming and carbonation processes canbecarried out continuously upon a continuous ow of saccharine juice toboth clarify the juice and remove the clarifying reagent there- `fromwithout interruption of the flow. Other and filtering; to provideheatlngvmeans which will not become corroded or clogged; -to providemeans for quickly and efficiently cleaning the tank and equipment afteruse; and to provide an agitating mechanism which will not be dangerousto clean-up men if accidentally started dur'- ing cleaning operations.

Other objects and advantages reside in th'e detail construction of theinvention, which is designed for simplicity, economy, and efficiency.These will become more apparent from the fol.- lowing description.

In the following detailed description of the in vention reference is hadto the accompanying drawings which form a part hereof. Like numeralsrefer' to like parts in all views of the drawings and throughout thedescription.

In the' drawings:

Fig. 1 is a side view of theimproved carbona-v tion tank;

Fig. 2 is anfenlarged vertical section Vthrough the Alower portion of4the tank;V

Figs. 3, 4,- and are horizontal cross sections', taken on the lines,3-3,4 4, and 5 6, respectively. v

The'entire mechanism is housedina vertically elongated tank iu having aconical bottom ||v dis:

charging into an elbow fitting I2. An'overnow line I 3 leads from theelbow Afitting I2 upwardly 'along -the tank to the desired solutionlevel therein thence turns downwardly to deliver the clari-f nedoutgoing -juice to any desired point. A discharge valve I 4 opens fromthe bottom o f they elbow tting l2.,

An agitator shaft I5 extends axially downwar through the top of the tankfrom a variable speed Il; The Shaft l5 is mounted in Suitable bearingsI1 on cross members IB in the tank A- its bottom. A vapor stack 25coinmur'iicatesthroughthe closed top of the tank I0 to carry spiralconveyor screw I9 surrounds the lowerportion of the shaft.

The conveyor screw is surrounded by a, relatively, closely tting risertube 2b which is open at both extremities. The tube-is supported fromthecross members I8 in any desired manner and extends'the full length ofthe screw I9.- An inverted, cup-shaped hood ZI is-supported above w theupperopen extremity of the tube.

It is desired to call .attention to the proportionate iengths f I thetank and' riser tube. It has been found' that in usual eld conditions atank 30 feet high with aconv'eyor screw and rise tube approximately 10feet long in its bottom produces the best results. This leaves. amplespace in the upper portion of the tank forl frothing and foaming withoutloss.

The juice to be @treated is fed directly' into the lower portion of theriser tube through a juice inlet 2K. 4A steam pipe 22,extends downwardlythrough the top of the tank and enters the riser tube at a point about Aofthe length n from the top 'of the tube. A milk-of-lime pipe 23 alsoextends downwardly from the top of the tank and enters the tubelilapproximately at its middle. A reagent pipe 24 extends downwardly in thetank and enters the riser tube near thevapors therefrom. `A pipe grid 26is placed in the bottom of the tank I0 immediately below,

the riser tube and is supplied with C Oz gas from a CO2 supply line 21.vare longitudinally slotted along their bottoms for theexit of the gas.circular'plate ,30 covers the mld-portion of the grid 26 to divert 'thebubbles from entering the riser tube 20.

' Operation During operation the juice level in the tank is maintainedat a point just below the'top of .the

riser tube 20 by the preset' overflow inthe over- Y ilow pipe I3.Saccharine juice, milkof-lime, steam and CO2 gas are constantly iiowingtothe tank throughtheir respective pipes, and the defe' cated juice isdischarging the overflow pipe I3;

The juice inthe tank is drawn downwardly, by

the suction created at the bottom of the riser tube 20 b'y the screw I9. `Fresh juice also is en# tering the riser tubevirom the inlet 28. Thejuices are intermixed and elevated by the action. of the screw. Asthejuices pass the outlet of the milkof-lime pipe 23, they pick up `thelatter.

The pipes of the' grid 26 from thetar'ik through The milk-of-lime isintimately intermixed with the juiceby the action of the screw. As theintermixed, limed 'juice passes the outlet of the steam pipe 22, itstemperature is immediately raised to the boiling point so that it willboil from the top of the tube 20 4against the hood 2l and into the upperportion of the tank. The quick use ofthe boiling temperature preventsthe formation .of bicarbonates and the resulting hard scale formationsin the evaporators and pans.

vThe vjuice will then be drawn downwardly about the tube 20 by theaction of the screw I9. y In moving downwardly it must passthrough themultitude of CO2 bubbles rising in the julice from the pipe grid 26.'I'he downward movement of the juice combined with the upward flow ofthe 4gas produces an intimate and complete contact between the lime andgas molecules to effect a complete removal of the lime therefrom ascalcium carbonate. It will also be noted that the lime Ymilk inendeavoring to drop by gravity in the riser tube` encounters upwardlyilowi'ng'juice. These conicting ows, against both the lime and the gas,greatly increase the eiiiciency of mixture.

'The calcium carbonate and the precipitant -juice migrate to the bottomof the tank vand from thence through the over ow pipe i3v` to suitablesettlers, lfilters or other treatment.

. It is to beunderstood that the above refers tol a selected sample ofthe juice. ,In actual operation, portions of the juice will returnupward through the agitation tubefor a second or third liming and flowdownwardly through the tank for precipitation.

Tests are made through suitably positioned testl cocks 29v to determinethe condition of the ially-positioned .riser vtube in the lower portionof said tank supported above the bottom thereof means for introducingjuice into said tube; me-

juice and the valves of the various supply pipes are' adjustedaccordingly to obtain maximum results.

vShould undue foaming occur, a`suitable foam retardant can be introducedthrough the pipe 24 -to counteract the diiliculty. The foaming; however;is usually'controlled by the action of the hood 2| which acts to throwthe violently boiling juice directly downward intov and onto the juicesbeing vcarbonated to cool the former and to `suppress the foam on thelatter.

If necessary, the tank may be drained by opening the discharge valve I4.t The tank may be xnediately and before it is intermixed with'the ankjuices. rThe liming and carbonation are herefore carried out incontinuous successive teps on the continuously ilowin'gjuices.

While 'a rspeciiic form of the improvement has been described andillustrated herein; it is desired to be' `understood'tl iat the same maybe without Ideparting'fifromlthe spirit of the inven' Having thusdescribed gthe invention, what is ,'"milk of llixnepipe-"so that itreceives its lime im-l ari'ed', withlnth'e scope ofthe appended claims,

claimed'and desired secured by Letters Patent is': '.-1..A liming tankfor sugar mills comprising: a vertically elongated tank; an open-ended,ax-

of-lime into said riser tube in upwardly spaced relation to the juiceinlet; and means for introducing live steam into said riser tube betweenthe lime inlet and theupper end of the tube.

2. A carbonation tank for use in sugar mills comprising: a verticallyelongated tank; an open-ended, axially-positioned riser tube in thelower portion of said tank supported above the bottom thereof; an overowdischarge leading from the lower end of said tank and positioned tomaintain the fluid level therein substantially at the top of the risertube; means for delivering juice into said tube near the lower endthereof; mechanical means in said tube for impelling juice upwardlytherein and creating a downwardly flowing current in the juicesurrounding said tube; means for introducing milk- .of-lime into saidtube in upwardly spaced relation to the juice inlet; means for heatingthe mixture of juice and lime as it approaches the upper end of thetube; and means adjacent the bottom of said tank for introducing CO2 gasinto the downwardly flowing juice. l

3. A combined liming and carbonation tank comprising: a vverticallyelongated tank; an open-ended, axially-positioned riser tube in thelower portion of said tank supported above the bottom thereof; anoverflow discharge leading from the bottom of said tank and positionedto maintain the fluid level therein substantially at the top of theriser tube; means for introducing juice into said tube near the lowerend thereof; mechanical means in said tube for impelling juice upwardlytherein and creating a downward overflow discharge leading from thelowerend of said tank and positioned to maintain the fluid level thereinsubstantially at the top 0f theriser tube; mechanical means in said tubefor impelling juice upwardly therein and creating a downwardly vflowingcurrent in the juice surrounding said tube; means adjacent the bottom ofsaid tank for introducing CO2 gas into the downwardly flowing juice;means for introducing milk-of-lime into said riser tube in spacedrelation to upper and lower ends thereof; a juice conduit entering'saidriser tube adjacent the bottom thereof and in downwardly spaced relationto the inlet for milk-of-lime for continuously supplying the juice to betreated thereto; .and means for heating the mixturev of juice and limebetween the lime` inlet and the upper end of the tube 5. A combinedliming and carbonation tank Y comprising: a vertically elongated tank;an

open-ended, axially-positioned riser tube in the lower portion of saidtank supported above the bottom thereof; an overflow discharge leadingfromv the bottom of said tank and positioned to maintain the Iiuld leveltherein substantially at the top of the riser tube; means for`introducing juice into the tube adjacent the lower end thereof,mechanical means in said tube for impeiling juice upwardly therein andcreating a downwardly owingcurrent in. the juice surrounding said tube;means adjacent the bottom of said tank for introducing CO2 gas into thedownwardly owing juice; means for introducing milk-of-lime into saidriser tube spaced upward ly from the juice inlet; and a conduit enteringsaid riser tube above the milk-of-lime inlet for supplying steam to theupper portion of the tube as a heating medium.

6. A combined liming and carbonation tank comprising: a verticallyelongated tank;- an

open-ended, axially-positioned riser tube in the lower portion of saidtank supported above the bottom thereof; an overflow discharge leadingfrom the bottom of said tank and positionedto maintain the uid leveltherein substantially at the top of the riser tube; mechanical means insaid tube for impelling juice upwardly therein and creating a downwardlyowing current in the juice surrounding said tube; means adjacent thebottom of said tank for introducing CO2 gas into the downwardly owingjuice; means for introducing juice into the tube adjacent the lower endthereof; means for introducing milkof-lime into lsaid riser tube at apoint spaced upwardly from the juice inlet; means Ifor heatfrom thebottom of said tank and positioned to maintain the uidlevel thereinsubstantially at the top of the riser tube; mechanical means in saidtube'for impelling juice upwardlytherein and creating a Vdownwardlyiliowing'current in the juice surroundingsaid tube; means for deliveringjuice` to the tube near the lower end thereof; means for deliveringmilk-of-lime to the tube above the juice inlet, means between the 4limelinlet and the upperV end of said tube 4for heating thel juice; a pipegridl in the bottom of said tank having gas discharge orifices in. its

-a downwardly flowing current in the juice suring the juice inthe tubespaced upwardly from the lime inlet; an inverted, cup-shaped hood oversaid riser tube for directing thelupwardly .discharging juice downwardlyin said tank.

= 7. A combined -liming and carbonation tank comprising:` a verticallyelongated tank; an open-ended, axially-positioned riser tube in thelower portion of said tank supported above the bottom thereof; anoverflow discharge leading from the bottom of said tank and' positionedto maintain the fluid level therein substantially at the top of theriser tube; mechanical means in said tube for impelling juice upwardlytherein and creating downwardly owing current in the juicesurroimdingsaid tube; means adjacent the bottom of said tank forintroducing CO2 gas into the downwardly flowing juice; iiieans fordelivering steam as a heating medium into the tube adjacent the upperend thereof; means for i introducing milk-of-lime into said riser tubespaced downwardly from the steam inlet: a juice conduit entering saidriser tube adjacent the bottom thereof in downwardly spaced relation tothe milk-of-lime inlet for continuously supplying the juice to betreated thereto; andan inverted;

cup-shaped hood supported above said riser tube to direct the upwardlyflowing juice downwardly in said tank about said tube;

8. A carbonation tank for use in sugar mills comprising: a verticallyelongated tank; an open-ended, axially-positioned riser tubev in thelower portion of said tank supported above the bottom thereof; an overowdischarge leading i tank fr introducing CO2- gas into the downward'-rounding said tube; an inlet pipe for juice com- 'municating with saidtube near the lower endl thereof; an inlet pipe forj-milk-o'f-limecommunicating with said tube spaced upwardly `from the juice inlet;means for heating the juice in the tube 'above the inlet formilk-ofalime; a pipe grid 'in the bottom of saidtank below said tubehaving gasdischarge orifices in its bottom; means for supplying COi gasto said grid; land baffle means below saidv tube for deflecting the d.4gas bubbles away from the lower end of said tube.

10. A combined liming and carbonation tank comprising: a verticallyelongated tank; an open-ended, axially-positioned riser tube in thelower portion of said tank supported above the bottom thereof 'an'overflow discharge leading from the bottom of said tank'and positionedto maintain the i'lui'd level therein substantially at the top of theriser tube; a Vertic'al screw conveyor in said tube for impelling juiceupwardly thereinand out of the top vof the tube andcreating a downwardlyilowing current toward the lower end of the tubein the juice surroundingsaid tube; means adjacent the bottom of .said

1y flowing juice; means for introducing milk-oflime into said risertube; a juice conduit entering'said riser tube adjacent the bottomthereof at a point spaced downwardly from themilk-of-fv lime inlet forcontinuously supplying the juice to be treatedintothe tube; aninlet forheat? ing^ steam communicating with said tube adja cent the top of thetube and spaced upwardly from the milk-of-lime inlet; a shaft extendingupwardly from said conveyor through the top of said tank; and a motormounted above said tank and being operatively connected with saidshaftto'rotate the latter.

ouvnn C. SWAN.

